The content delivery network (CDN) has become a main platform for media content delivery. The user generated content (UGC) service networks such as YouTube, YouKu, 56, and Tudou are popularized, and have absorbed plenty of users who share content. Currently, such services are primarily implemented through a distributed network structure where the domains are managed separately. The network structure comes in two modes. One mode is: A domain management server is set in each domain to manage the running conditions of the nodes in the domain, and a central server is set to manage the domain management servers and implement hierarchical management. That is, the shared content in the network is delivered to lower layers through the central server layer by layer so that the content is stored on the node (i.e., an edge server (ES)) in the domain near the user. In this way, the user can obtain the desired content from the ES quickly. The other mode is: The performance of all the nodes in the distributed network is measured, and the nodes of better performance are selected as super nodes. The super nodes manage the nodes in the domain, and no central server is required for managing the super nodes. The second mode simplifies the hierarchical management structure, and is known as a fully distributed network structure.
In the existing fully distributed network structure, the user's requirements for the node that stores content vary geographically, namely, the user can request or store content on the node in the user's own access domain. In such a network structure, two distributed hash table (DHT) algorithms need to be constructed to implement the global content management and the node management of each domain. The DHT algorithms generally applied in the existing distributed network structure include Chord, CAN, Pastry, and kademlia (KAD). The KAD is a topology of a totally new DHT algorithm which uses a special exclusive-or (XOR) algorithm as a distance measurement basis, and improves the speed of querying routes significantly.
In the process of implementing the present invention, the inventor finds at least these defects in the prior art: The node distribution based on the node ID calculated through the existing DHT algorithm is rather uneven, which tends to cause load imbalance on the node. Meanwhile, each node needs to maintain table entries of two structured networks, and the information maintained by certain nodes is redundant and leads to unnecessary overheads.